Currently available subdermal needle electrodes (i.e., conventional subdermal needle electrodes) are typically provided in the form of an assembly consisting of a metal needle electrode (stainless steel, platinum, tungsten etc.), lead wire, connector fixedly joining the metal needle electrode to a first end portion of the lead wire, and an electrical plug connected to a second end portion of the lead wire. This assembly is referred to herein as a subdermal needle electrode cable assembly, which is typically offered as a single subdermal needle electrode cable assembly in a sterile-packaged or a set (e.g., pair) of subdermal needle electrode cable assemblies in a sterile package.
Subdermal needle electrodes are used in neurological and neurophysiological studies for recording a variety of types of neurological and neurophysiological signals. Examples of such signals include, but are not limited to, electroencephalogram (EEG) signals, spontaneous or triggered electromyogram (EMG) signals, somatosensory evoked potential (SSEP) signals, transcranial motor evoked potential (tcMEP) signals, brainstem auditory evoked potential (BAER) signals, and visual evoked potential (VEP) signals. The studies generally occur in various environments such as, for example, a hospital intensive care unit (ICU), an in-patient setting (e.g., clinic), and in an operating room (e.g., at a hospital). Intraoperative neuromonitoring (IOM) is a common type of intra-operative neurophysiological study and can include any combination of EEG, SSEP, tcMEP, EMG, BAER, or VEP signal monitoring during neurosurgery, orthopedic surgery, cardiovascular surgery and neurovascular surgery. During such types of surgeries, neural structures are often at risk for loss of function and, thus, the benefit of monitoring such function with IOM.
Intraoperative neuromonitoring has developed rapidly over the last several years. Furthermore, it has become a standard aspect of care in the modern surgical procedures outlined above. Intraoperative neuromonitoring is required in a considerable number of surgical procedures every day in US and many other countries around the world. Most of the procedures require 20-40 subdermal needle electrodes. Thus, a very large number of subdermal needle electrodes are used daily throughout the United States as well as many other countries around the world.
In one example, subdermal needle electrodes are applied through the skin to reach the target muscle groups for EMG recording and subcutaneously in the scalp for SSEP recording. Optionally, electrodes can also be applied subcutaneously in the scalp for transcranial motor stimulation. Intraoperative neuromonitoring is an extremely important tool for providing the surgeon with constant functional assessment of the central and peripheral nervous systems. Subdermal electrode needles are not reusable and, thus, require disposal after use. Because subdermal needle electrodes need to penetrate the skin in the patients, they must be considered to carry bloodborne pathogens after use.
Currently available FDA-approved subdermal needle electrodes have a protective cover over the needle to keep the needle sterile in its package and prior to use as well as prevent needle sticks prior to its use. However, they do not have any safety features to prevent or limit the potential for needle sticks once they are removed from a patient. With the considerable number of intraoperative neuromonitoring procedures in the US and worldwide, needle stick incidents from subdermal needle electrodes by healthcare professional and surgeons are not uncommon.
To handle a total of 20-40 single electrodes or paired electrodes in a time-critical operating room, a high rate of needle stick incidents occur to neurophysiologists, neuromonitoring technicians, nurses, anesthesiologist, surgeons and room helpers. This type of surgery requires teamwork with many surgical staff members working simultaneously on the patient especially at the beginning and end of surgery. The needle electrodes must be removed from the patient before recovery from the anesthesia. This is an extremely hazardous procedure when 20-40 single or 10-20 pairs of subdermal needle electrodes are individually removed from the patient's body. The removed needle electrodes are open and exposed until their final collection and disposal. During this time, all of the surgical staff are at risk of a needle stick, which could potentially transmit hazardous bloodborne pathogens and/or infectious diseases. Examples of such hazardous bloodborne pathogens and/or infectious diseases include, but are not limited to, Human Immunodeficiency Virus (HIV), Hepatitis B, Hepatitis C and Creutzfeldt-Jakob Disease (CJD).
In October of 2000, “The Needlestick Safety and Prevention Act” (i.e., the ACT) was passed in the United States Senate (October 3rd) and United States House of Representatives of The United States of America (October 26th) in United States Congress. In response to this law, the US Department of Labor revised “The Bloodborne Pathogens Standard” in January of 2001. The Act presents various aspects of the requirement for use of engineering and work practice controls to eliminate or minimize employee exposure to bloodborne pathogens. The Act presents information relating to changes in technology that eliminate or reduce exposure to bloodborne pathogens. The Act states that numerous studies have demonstrated that the use of safer medical devices, such as needleless systems and sharps with engineered sharps injury protections, when they are part of an overall bloodborne pathogens risk-reduction program, can be extremely effective in reducing accidental sharps injuries. The Act also states that, in March of 2000, the Centers for Disease Control and Prevention estimated that 62 to 88 percent of sharps injuries could potentially be prevented by the use of safer medical devices.
The traditional design of the subdermal needle electrode has existed for many years without change. More specifically, no currently-available FDA-approved subdermal needle electrode have any type of safety device that prevents or substantially limits the potential for sticks by the needle electrode after it has been removed from a patient. Therefore, a subdermal needle electrode cable assembly that overcomes drawbacks associated with currently available subdermal needle electrode cable assemblies not preventing or substantially limits the potential for needle sticks would be advantageous, desirable and useful.